Tactile discrimination as a diagnostic indicator of cognitive decline in patients with mild cognitive impairment: A narrative review

• Published in: Heliyon 2024-05, Vol.10 (10), p.e31256-e31256, Article e31256
• Main Authors: Xu, Jinan, Sun, Yuqi, Zhu, Xianghe, Pan, Sipei, Tong, Zhiqian, Jiang, Ke
• Format: Article
• Language: English
• Subjects: Alzheimer disease; Alzheimer's disease; clinical examination; cognition; Cognitive assessment; cognitive disorders; memory; Mild cognitive impairment; Review; Tactile discrimination
• ISSN: 2405-8440; 2405-8440
• DOI: 10.1016/j.heliyon.2024.e31256

Tactile discrimination, a cognitive task reliant on fingertip touch for stimulus discrimination, encompasses the somatosensory system and working memory, with its acuity diminishing with advancing age. Presently, the evaluation of cognitive capacity to differentiate between individuals with early Alzheimer's disease (AD) and typical older adults predominantly relies on visual or auditory tasks, yet the efficacy of discrimination remains constrained. To review the existing tactile cognitive tasks and explore the interaction between tactile perception and the pathological process of Alzheimer's disease. The tactile discrimination task may be used as a reference index of cognitive decline in patients with mild cognitive impairment and provide a new method for clinical evaluation. We searched four databases (Embase, PubMed, Web of Science and Google scholar). The reference coverage was from 1936 to 2023. The search terms included “Alzheimer disease” “mild cognitive impairment” “tactile” “tactile discrimination” “tactile test” and so on. Reviews and experimental reports in the field were examined and the effectiveness of different types of tactile tasks was compared. Individuals in the initial phases of Alzheimer's spectrum disease, specifically those in the stage of mild cognitive impairment (MCI), exhibit notable impairments in tasks involving tactile discrimination. These tasks possess certain merits, such as their quick and straightforward comparability, independence from educational background, and ability to circumvent the limitations associated with conventional cognitive assessment scales. Furthermore, tactile discrimination tasks offer enhanced accuracy compared to cognitive tasks that employ visual or auditory stimuli. Tactile discrimination has the potential to serve as an innovative reference indicator for the swift diagnosis of clinical MCI patients, thereby assisting in the screening process on a clinical scale. [Display omitted] •The acuity of tactile discrimination is definitely declined with advancing age.•This task is better accurate than visual or auditory test in the elder population.•MCI patients exhibit an impairment in the task involving tactile discrimination.•This subtle distinction may be a potential indicator for diagnosing MCI patients.